I have a question about the discrepancy in the grid import/export numbers between the Enphase dashboard and the summary dashboard in the Enphase integration.
Data is captured for the very same day (July 10th), to make sure all data points were accounted for
I can clearly correlate solar production, battery charge / discharge, home consumption (within reason) but for the life of me I cannot figure out the discrepancy for the grid import/export values. The net is correct (3.7kWh) but the absolute values are off by 4.3kWh for some reason.
• Enphase: 37.7kWh exported, 34kWh imported, net 3.7kWh
• HA: 42kWh exported (+4.3), 38.3kWh imported (+4.3), net 3.7kWh
Another day, and also discrepancy
• Enphase: 40kWh exported, 29.2kWh imported, net 10.8kWh
• HA: 45.5kWh exported (+5.5), 34.6kWh imported (+5.4), net 10.9kWh
It seems to be all over the place and I do not seem to figure out what the delta is and where it is coming from. I tried to see whether battery is somewhat responsible for that delta, but I cannot work out how battery charge / discharge number would influence import / export from the grid in this case.
Any thoughts would be really welcome here. It is driving me insane!
Batteries on 3 phase systems can not transfer energy from 1 phase to another phase. In EU countries with phase balancing grid meters, the grid is used as a virtual exchange. A battery will export to to grid om one phase if the demand on another phase is higher then it can supply on that phase. The phase with the demand will pull the extra amount needed from the grid. Energy transferred between phases… The grid meter will balance it, regulations in EU countries. But Envoy net-consumption CT will see it outgoing to the grid on one phase and incoming from the grid on another phase. Hence to additional amount for grid import/export.
If not, then at least you know how it works over here
thanks @catsmanac but I am US based so perhaps similar principle applies, but from what I can tell the numbers reported by Enphase natively are very close to what my utility is reporting. The discrepancy in the Enphase dashboard in HA is the part that makes no sense to me. It seems that the HA dasboard uses some different calculation routine to establish what is being exported and imported. Why, I do not have a clue.
I must have asked a really tricky question … I was hoping for the Enphase support team to be able to at least provide some guidance. All they do is point back to this forum after all.